Buildings are often constructed with prefabricated sections such as walls, for example. The use of prefabricated walls allows for economies of scale from a production line to be brought to the construction of buildings.
Wall sections typically have top and bottom timber plates which are joined together by braces. These braces are typically fixed to the plates with nails that pass through the plates into the braces in the axis of the braces. Typically, two nails will be used for each brace. The braces are typically rectangular in cross-section and the two nails are separated by approximately one third of the length of the rectangular cross-section of the brace.
The frames are also typically fabricated while lying flat on a fabrication bed. Therefore, the two positions of nails which fix the brace to the plate will correspond to two different elevations above the fabrication bed.
GB 1202278 discloses a framing machine for use in constructing wall frames. The machine has a pair of pneumatically operated nail guns mounted on pivots at the side of the wall framing machine. The gun moves approximately vertically, but in an arc beside the frame. A vertical ram actuates the pivots to change the angle of the gun and the height at which the gun contacts a plate of the wall frame. The adjustment of the height of the nail gun at the plate allows a single gun to fire pairs of nails through the plate into a common brace.
U.S. Pat. No. 3,848,798 and U.S. Pat. No. 4,031,604 also relate to a machine for constructing wall frames in which plates are nailed with pairs of nails to braces. These documents also disclose a nail gun mounted on a pivot and actuated by a ram. In this case the pivot is parallel to the brace so the angle at which the nails are applied to the brace will be slightly off-parallel to the brace.
A problem with these apparatus is that while pivoting of a nail gun allows adjustment of the position of entry of nails into a brace, it suffers a problem that the nails will not be aligned with the brace. Instead, the nails will radiate from the pivot.
Another problem with these apparatus is that the pivot needs to be some distance from the frame being fabricated if the nail is not to be at too obtuse an angle of the axis of the brace. This pivot arrangement requires a considerable amount of space which places design constraints on the fabrication apparatus and may require a considerable amount of factory floor space.
Nail guns are typically used in the fabrication of wall sections as nail guns provide a very rapid nailing operation.
One way to supply a large number of nails to a nail gun, as is suitable for a production line situation, might be via a hose through which the nails pass. The hose would be supplied by a feeder which is in turn supplied by a bulk supply of loose nails which are vibrated or shaken in a ‘tumbler’. The tumbler serves the purpose of rumbling or tumbling the nails into an alignment in which they fall down a feed shute for the hose. In this arrangement, the hose may require careful arrangement so that the flow of nails is not restricted, which can in turn place constraints on a design of the framing fabrication apparatus. The use of a nail feed hose may also place constraints on movement of the nail gun if the hose is to be unrestricted. Also, the ‘tumbler’ is likely to be large and bulky and this may also place constraints on the design of the apparatus.
Other types of nail guns might be supplied by a magazine of nails. A magazine may typically hold forty nails. This arrangement allows more flexibility in the design of framing fabrication apparatus and also allows ready adjustment of the position of the nail gun. However, a problem with magazine supplied nail guns is that the magazine may hold a relatively small amount of nails for production line applications. Frequent replacement of the magazines may be required.
Walls are typically constructed by adding braces, braces and other sections to the frame at one end. The frame is progressively moved away from that end as sections are added to the frame. Typically, roller supports are provided to support the frame at the outer edges by the plates. Rollers allow the frame to be moved easily.
Wall frames might be made of timber with various thicknesses. The variation in thicknesses may affect the spacing of nails in the braces if the apparatus is to cater for a range of timber thicknesses. For example, a framing apparatus adjusted to cater for a relatively thin timber will place the nails relatively close together in a relatively thick timber.
U.S. Pat. No. 3,873,015 discloses a machine for constructing wall frames. This machine provides two nails at different heights in the plate by having two nail guns at different points along the length of the frame. A brace is nailed to the plate by the first gun which is at a lower height, and then the brace is moved along to a second gun which is positioned at a higher point on a plate. However, the nail guns of this machine do not move at all.
Some wall framing apparatus are known which use a hose feed nail gun apparatus with an adjustable height for the placement of nails in the braces relative to a fabrication bed. These apparatus have a ram which drives a nail which is dropped in front of the ram into the timber. The nail hose is fed by a ‘tumbler’ which agitates a box supply of loose nails into a feeder for the nail supply hose. The nail ram is pivotally mounted with the pivot at some distance from the frame being fabricated so the position of the nails in the brace can be adjusted by pivoting the nail gun.
While the pivoting allows the position of entry of nails into a brace to be adjusted, it suffers a problem that the nails will not be aligned with the brace. Instead, the nails will radiate from the pivot.
Another problem with this apparatus is that the pivot needs to be some distance from the frame being fabricated if the nail is not to be at too obtuse an angle of the axis of the brace. This pivot arrangement requires a considerable amount of space which places design constraints on the fabrication apparatus and may require a considerable amount of factory floor space.
A further disadvantage of the above prior art devices is that they are configured with a fixed position switch which confines the operator to one location.
This increases the travel time around the working area as the operator is required to return to the central position of the machine to the press switch. Also, hands free operation is not possible when the operator is required to push the switch. This can lead to an inaccuracy of work when lining marks up on the timber.
It is an object of the present invention to provide an apparatus for fabricated frames which overcomes or mitigates some of the aforementioned problems with existing apparatus for fabrication of frames, or at least to provide the public with a useful choice in apparatus for fabrication of frames.
It is a further object of the present invention to provide an apparatus for fabrication of frames in which the nailing of braces to frames is provided and which utilises a minimal number of nail guns and also allows relatively large scale supply of nails without the need for frequent replacement of nail supplies.
It is a further object of the present invention to provide an apparatus for fabrication of frames that allows a relatively large supply of nails to be supplied to nail guns in a relatively compact form.
It is a further object of the present invention to provide an apparatus for fabrication of frames which allows adjustment of the elevation of the position of the nails relative to a fabrication and uses a nail belt to supply the nail gun.
As used herein the term ‘brace’ should be understood to refer to any framing perpendicular to the plate(s) of the frame.
As used herein the term ‘nail belt’ refers to a plurality of nails attached together for feeding and handling purposes but suitable for supplying the nails to a nail gun.
As used herein the term ‘coil’ used in conjunction with ‘nail belt’ includes a roll, spool, reel or such like of the nail belt. It is envisaged that the term also includes the nail belt being flaked. Here flaked refers to a zig-zag stacking of successive layers of the belt.
As used herein a ‘single nailing operation’ includes the addition of nails in combination to a frame even if the nails are added sequentially. For example, pairs of nails may be used to provide additional strength.
As used herein, the terms ‘horizontal’ and ‘vertical’ or grammatical variations mean substantially horizontal and substantially vertical so that minor variations or deviations from horizontal or vertical are included. Also, the terms refer to alternative alignments or orientations to ‘horizontal’ or ‘vertical’ where alternative provisions for gravity are apparent to those skilled in the art.
As used herein, the term ‘planar’ and ‘selected plane’ refers to a plane in which a frame or a side of a frame might be considered to lie. A frame formed from members is considered to be able to lie in a given plane even though the members have finite width and spaces are formed between members in that frame.
As used herein, the term ‘processor’ refers to a computer, microprocessor, microcontroller, programmable logic device or any other processor known to those skilled in the art. The term ‘processor executable instructions’ stored on a processor readable medium is intended to include any instructions or configurable information that is readable by the ‘processor’. This may include a medium as simple as gates or switches of a programmable logic device circuit.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
It is acknowledged that the term ‘comprise’ may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term ‘comprise’ shall have an inclusive meaning—i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term ‘comprised’ or ‘comprising’ is used in relation to one or more steps in a method or process.
Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.